Distillation apparatus for refining fats and oils



P 1952 J. E. THOMPSON 2,611,741

DISTILLATION APPARATUS FOR REFINING FATS AND OILS Filed Nov. 26/1948 INV EN TOR.

12 BY gm Patented Sept. 23, 1952 DISTILLATION APPARATUS FOR REFININGFATS AND OILS John E. Thompson, Chicago, .111.

Application November 26, 1948, Serial No. 62,077

My new and novel invention relates generally to the art of refining oilsand fatty material and more particularly to the improvedprocess of and aClainjis; (01. 202187) Heretofore, the generally accepted method ofdeodorizing such oils has been accomplished by the use of (1) the batchsystem, in which the tank is filled with a, charge of cold, raw oilwhich is thereupon subjected to the desired operating vacuum. It is thenheated by means of heating coils within the tank, while at the same timestripping steam is forced through the body of oil, or (2) the continuoussystem, in which a similar efiect is wrought on a continuous basis,using stripping steam forced through heated oil.

' By the batch method, the temperature is gradually built up to themaximum in the presence of vacuum, and subsequently, some of thevolatile constituents, including air, are released and escape from theoil before it reaches its maxi-'- mum temperature. This is an advantageto the extent that the oil is not highly heated in the presence ofoxygen and thus tends to prevent oxidation. However, heating the oil inbulk is a relatively slow process and has the disadvantage that certainother chemical changes may take place as a result ofthe extended heatingperiod.

Moreover, only the top-most part of the oil is subjected to full vacuumsince all other portions of the body of oil are under some hydrostaticpressure. The deodorization period by this process is undesirablyextended with the adverse results referred to.

Various attempts have been made to make use of a continuous system ofdeodorization by heating the raw oil and then exposing it in relativelyshallow layers of large. area to sub-atmospheric pressure, while, at thesame time contacting the oils with stripping steam with the thought thatcomplete deodorization mightthus be brought about in a much shorterperiodof time than would be the case with a batch system, therebyminimizing the deleterious chemical ac- ,2 tlons produced by subjectingthe body of the oil to a prolonged high temperature heating. A majorimpediment to the success of such continuous systems has been the lackof provision for the initial release of air and certain undesirablevolatile constituents at low temperature; or the use of highlycomplicated systems attempting to remove the air and certain undesirablevolatile constituents, the use of which introduced additional adverseresults.

An additional disadvantage to existing systems of deodorizationemploying steam to strip undesirable volatiles from the raw oil arisesout of the extremely costly and bulky equipment necessary to maintainhigh vacuum, while disposing of the large volume of stripping steam usedin these methods. 1

The major objects of mypresent novel invention overcome theaforementioned disadvantage of prior products by causing the raw oil,which is to be deodorized, to pass continually over surfaces heated tosuccessively higher temperatures to remove a portion of the vapors; andespecially the air, before the oil reaches the high temperaturenecessary to complete deodorization. The oil passing over these heatedsurfaces is exposed to high vacuum in the form of an extremely thin filmso that stripping steam is unnecessary to accomplish release of theundesirable'volatile materials. With this method, steam consumption and.operating costs and initial capital investment are reduced as comparedwith prior methods, and physical size of the apparatus is greatlyreduced.

Other and further objects of my novel device will become apparent fromthe specification and the appended claims, reference bein made to thedrawings and the numerals of reference thereon.

On the drawings:

Fig. 1 is a diagrammatic longitudinal cross sectional view of my device.

Fig. 2 is a cross sectional View taken substantially on the line 2--2 ofFig. 1 and looking in the direction of the arrows. I

Referring to the drawings, numeral II represents an elongated aperturedtube or tubular member which is sealed at one end, which in a preferableform is the top, in any suitable manner such as by means including anapertured weld flange, plate, disk or member such as I have illustratedas numeral [3 and which is preferably welded to an end periphery of'tubeI l. The tube II is preferably composed of some non-corrosive materialsuch as stainless steel orthe'like. At the other end, which ispreferablythe bottom,

tube H is sealed by a weld flange, disk or plate 52 by means such asweldin V Numeral i6 represents an elongated tubular member, pipe orhollow column which is closed at one end by a preferably integral endportion or plate l5, which is integral with the longitudlnal walls ofthe tube M. The tube i l, at a preferably upper end thereof, is sealedby an apertured weld flange, plate or disk is, which-in a preferred formis adapted to form an airtight seal around the periphery of the upperend of the tube [4 by means such as welding. Portions. i

of the column M are disposedwithin the tube ,H and a mounting of saidtube hi is provided by preferably welding portions of its outer wall tothe aperture defining edges of the flange 13, .as illustrated in Fig. l,

Securely mounted, by welding or the like,

around the tube H at one end thereof isan apertured flanged member i9whose flanges on a preferably lower surface welded or equivalentlyunited to the preferably upper abutting face of flange 2. similarlyaweld ilange i8 is securely .mo ted on the other end of tube H, asillustrated and the face thereof abutting disk i3 is preferably'weldedthereto, In preferably a like manner-mange r'nernber i7 is welded todisk or sealing plate is. The members or weld flanges 11,18 andls'respectively, in the modified form illustrated add rigidity to theplates or disks l8,

havefillustrated in Fig. 1.

The outer surface'of the tube ill which is disposed within the tube llprovides a surface on which co ndensable gases will liquefy The chamberwhich is formed between the walls of the tube Hand the walls of the tube[4, and which is limited on its opposite ends, by the disks 4 ture.Sealing said pipe 23 to said tube 1 I in an air tight seal in a sealingring or suitable equivalent 2 i which may be disposed along the outersurface of the tube H as illustrated in Fig. l. Preferably at the upperend thereof, the pipe or tube l 1 has another aperture in which ismounted a communicating conduit, pipe or nipple 25, which communicateswith the chamber or vacuum' compartment 20, and which .is preferablysealed by means of a sealing ring or other suitable means 26 so that anair tight seal is formed The nipple .25 is communicatively conmeans (notshown) preferably by means of a .weldiflangefifi. R'igidly disposedalong the inner surface of tube I i, preferably substantially adjacentto the upper end thereof, is a hollow annular pipe cordistributor 21which is preferably disilsta ndlz, provides avacuum compartment. To

facilitate the condensation of gases on the outer surface of the column5, said column should be sl ffiei nl la to b in e es 'a b ima o to theinner surface of the tube, so that fluid eel les liberat s wi ea l @omConta w th said u fa Qumra M an na ur n the liquid film of fat.Preferably at the lower end the a P e 21 hich ma b optionally L-shapedand disposed as I have illustratedin Fig. 1 is rigidly mounted in thepipe of tube ii and is sealed air tight, by anysuitable means such aswelded sealing rings or their equivalent which I have numbered 22. Thepassage of the pipe, conduit or tube 2! is communicatively connectedwiththe vacuum chamber, and preferably a vacuum pump or some other vacuumdevelopinerm an (nq s onni is .c mmn ca v y o nected Withthe pipeZl sothat anymaterial collecting in the bottom of the chamber 28 will bedrawn through said pipe into an appropriate collecting chamber orelement (not shown).

Preferably near the upper end thereof, the tube II is apertured and afeeding means; conduit, pipe or tube 23 islrigidly mounted in saidaperposed adjacent portions of the inner face of the .wallsoftube .i I,and which has a plurality of preferably downwardly opening holes orapertures 28,,said holes or apertures preferably being substantiallyuniformly spaced horizontally. The pipe 23 is 'communicatively connectedwith said distributor 2'1 as illustrated in Fig. 2.

The inner portion of the pipe carries a preferably integral curvedflange orlip 4! which is curved downwardly .so that any materialdropping on. said flange willbe deflected away and past the opening ofthe co'nnnunicating' means 25. Obviously such deflection may beaccomplishedin a variety of manners but I have found the aboveitolbe'the simplest.

Another aperture in the wall of the tube H :providesthe means throughwhich a communicating pipe 29 extends into the chamber 20. Saidcommunicating pipe or tube 23 at the inner end thereof .carriescatchbasin or apertured pan 3,0 towhi'ch said pipe 29 is lcommunicativelyconnected, The pipe 2-9 is appropriately sealed to form an air tightseal with thetube H by means of suitable memberssuch as sealing rings orthe like 3| which are preferably weldedto the conduit 29 and portions oftube H. The basin 30 is positioned. and rigidly mounted at preferablythe lower end ofpi'pe 1 ,4, said basin 39 being preferably of a diametergreater than said pipe I4 so that the adjacent end pfthe column orpipe Mis disposed within the opening in said basin 30. A suitable exhaustmeans is communicatively connected to the pipe 29 to withdraw any naterials collected in pan orbasin 36.

{Through one of the apertures in the flange or plate 15 a substantiallynarrow and elongated P o l q du i? xte ds a d te m a es p erably.adjacent theendiportion 15 of the tube ill. pipe is sealed, inpreferably an air tight s alsaid-ape ur by an ta e n uc as an annularsealing ring which may be welded oiequivalently united to portions oftheconduit 32 and the weld flange L6, as illustrated in theupper'portion of 1. Mounted in another aperture of the disk lB is acommunicating pipe or conduit as which is adapted to conduct away fromthe space formed within the pipe l4 any yolatile material. To form apreferably air tight sea-La suitable sealing ring 45 may be employed,said ring preferably being welded to the flange lliuahdthe' eon'duitfiflv Bigidly mounted-and around portions of the outer surface of tube ii isafpreferably annular trough-shaped jacket or channel 35' which isconnected along the ,inner'edgesthereof to the tube ll by a means suchas welding to form complete and air tight seal betweenv the inner edgesof the annular jacket and the outer surface portions of the tube l I. Itshould be understood that any suitable and equivalent means of mountingthe steam jacket 35 or for providing equivalent heat may optionally beused. Communicatively connected with said jacket are a pair of pipes orconduits 36 and 3'! one of which is an inlet pipe and the other of whichis an outlet pipe; Preferably an annular jacket 38 is rigidly mountedaround the tube H by any suitable means such as by retaining members 39.The jacket 38 is spaced from the jacket 3,5 preferably being positionedbelow said last mentioned jacket. Mounted in said jacket are a pluralityof highly electrical resistant wires or heater elements the terminals ofwhich are electrically connected to a suitable source of powerdesignated as 40, for example, an electric generator (not shown).

The following is a brief description of the operation of my noveldevice, and it is to be understood that although variations in thestructural elements may occur, the concept herein embraced relates tomany modifications not specifically herein described.

The fatty material being preferably in liquid form is forced intodistributor 21 through the conduit 23. At the time of entry into thedistributor, the fatty material is drawn downward by means of gravity.The apertures 28 in the distributor 21 are positioned adjacent the innerwall of the tube II. As the fat then is drawn down by gravity, orequivalently forced from said distributor, it forms a film along theinner wall of tube II, said film of fatty material being preferably,drawn downward by gravity. As the film of the fatty material advancesalong the inner wall of pipe II it is deflected away from the openingwhere the pipe or nipple 25 communicates withthe chamber 38 by means ofthe flange or lip 4| which directs the flow of material around theaperture in which said conduit 25 is positioned.

Preferably steam is supplied from an outside source going into thejacket 35 through the pipe 36 the condensate leaving through pipe 3which pipe is connected to a suitable exhaust pump (not shown). Asthefilm of moving fatty material comes into contact with the portions ofthe jacket heated by virtue of the steam which .is passing through thejacket 35, it becomes subjected togradually rising temperatures whichpreferably, at the highest temperature, substantially approximates thetemperature of the steam supply. During this initial heating certainvolatile adulterants of the fatty material are liberated because of thatheat. As the film continues to advance it comes into contact withportions of the tube l I which are heated because of the electric heaterunit 38 and there less-easily liberated adulterants are liberated. Thegradient of temperature which is established by this noveldeviceprovides for the film of fat coming into contact with anincreasingly higher temperature as it is preferably gravity drawn alongthe inner wall of the tube IL Thus volatile fluids, which would causeobjectionable substances to be produced in the fat if driven off at ahigh temperature, are driven from the advancing and moving fat film at arelatively low temperature. In this novel device dissolved air,non-condensable gases, and more volatile products are driven from thefilm of fatty material as it passes the steam jacket portion of the.column or tube H. The

air and non-condensable fluids pass upward through the preferablyannular space 20 and they are drawn out ofthe vacuum chamber 20 throughcommunicating'pipe or nipple 25.

A coolant or refrigerant is circulated through the column or pipe 14 'bybeing introduced through pipe 32 preferablyinto the bottom of the pipeor container M. A suitable coolant or refrigerant which has thus beenadmitted into the chamber formed within the pipe I4 is liberated at theopposite end of pipe 32 and circulated in said column thereby causing acooling of the walls of the pipe l4; As said coolant or refrigerant isheated it is removed from the chamber formed-within pipe l4 out of theap-' paratus through communicating pipe 34.

The outer surface of the pipe l4 disposed withinthe tube ll. forms acondensing surface, and condensable gases which are liberated from thefilm of advancing adulterated fatty and contaminated materiaL'arecondensed onthe outer surface of the pipe or column M. It is preferableto have the outer surface of column l4 relatively near the inner surfaceof pipe H for reasons heretofore indicated. Said condensable gasesare-carried along the surface of column M by means of gravity,preferably, and drop into the basin or pan or collecting element 30 andare withdrawn from my novel apparatus and-device through thecommunicating conduit or pipe- 29. Y Y

As the film of fat advances, the impurities being discharged asdescribed,.it moves to the bottom of the column or tube II and collectsin one end of the tube I l, which provides a reservoir, against theplate or disk l2, the fat is drawn from the device as a purifiedmaterial, through the outlet pipe 22. 7

In the modified form which I have described I have illustrated anapparatus which is adapted to liberate objectionable material from thefat continuously. However, this method may easily be adapted for use inthe batch-wise method of purifying fats or fatty materials.-

In one modified form adapted for treating adulterated fatty materialsbatch-wise, the lower or end portions of the vacuum chamber 20 may beenlarged at the region indicated as 41 so that said enlarged portionswill hold substantially the amount of a single batch. Fatty material isthen introduced through the pipe 23 and distributed along the innerwalls of pipe ll through distributoril,collecting in the enlargedportion 41. During this introductory process no heat is supplied throughthe heater 38. In this modified form the use of heat furnished throughsteam jacket 35 may be dispensed with entirely.

The fat which has collected in the enlarged portion at 41, is thencirculated and pumped back to pipe "23 at a preferably uniform rate.During the re-circulation process, heat equivalent to that produced bythe steam jacket 35 may be applied to the re-circulated fat before thesame is reintroduced into the distributor 21.

In this modified form the electrically resistant coils 48 which form theheating elements are disposed along the outer surface of the tube H toestablish a heat gradient. Thusly fat which is now free of the easilyremoved volatilates is distributed along the inner surface of the pipe Hand is exposed and subjected to a relatively high heat gradient whichwill cause the driving voff of the volatilates not driven oifduring there circulation of the fiat jfrom.the:tube H to the pipe 23.

It should be understood that although the volatilates which are removedfrom the finished fat are referred to as obnoxious adulterants andimpurities, that these are only'impurities and adulterants in the sensethat they :are undesirable in the "finished 'fat ,product.

It is an embodimento'f this invention -to,pro vide a means so that'someof these impurities or adulterants may be easily recovered inasmuchas-the volatilates, which although undesirable in the finished fatproduct, contain valuable materials, generally fatty acids, whichordinarily sell for ahigher price than the finished fat.

As many'changes could be made inthe above construction, and as manyapparently widely different embodiments of my invention within the scopeof the claims could :be constructed without departing from the spiritand scope thereof, itis intended that all matter contained in theaccompanying specification shall be interpreted as illustrativeandnot'in a limiting sense.

I claim:

1. In a device for .the continuous removal of volatile elements fromfats and'the like, an outer housing providing the outermost wall of avacuum chamber and providing an inner surface along which fats will flowdownwardly; pipe means extending through said housing for introducingthe unfinished fat into upper portions of said vacuum chamber; acircular conduit having a plurality of holes and being connected to saidpipe means for distributing said fat over the upper inner surface ofsaid outer housing; a steamheaterdisposed around said vacuum chamber andbeing adapted to heat portions thereof to the approximate temperature ofsaid heater means; an electrical heater disposedaround portions of saidvacuum chamber below said primary heater and being adapted to heatportions thereof .to substantially the temperature of said second heatermeans,-said primary heater bein adapted to heat the vacuum chamber totemperatures which are lower than the temperatures of said secondheatena condenser tube mounted in said vacuiun chamber and extendingoutwardly therefrom and providing a surface on which volatilized fluidsmay condense; the heat from said second heater being adapted to driveimpure fluids from the fat not driven on by the heat produced by saidprimary heater; an exhaust nipple adapted to withdraw from said vacuumchamber all non-condensabie fluids, the condensable fluid impuritiesbeing condensable along said condensing surface; a lip in the path offat flow for precluding entrance of fat into said nipple; afiuidcollection means adapted to collect the condensed fluid impurities andconduct them out of said vacuum chamber and extending through said wall;a reservoir in said vacuum chamber into which thefinished fat may becollected; and conduit means connected with said reservoir for removingthe finishedfat and extending through said Wall.

2. In a device for removing impurities from edible fats and the like, anoutermost elongated vertically disposed side apertured tube housinghaving sealing elements secured on its opposite ends, the upper of saidsealing elements being apertured; an upper steam heating element mountedin heat exchange relation with an intermediate portion of said tubehousing; a lower electrically energized heating element in heat exchangerelation with a portion of the walls of said tube housing and beingdisposed-below said steam heating element; an elongated verticallydisposed condenser tube mounted concentrically within the chamber ofsaid tube housing; conduits extending outwardly from the upper end ofsaid condenser tube and'adapte'd to conduct and circulate a flowablecooling-medium through said condenser tube; an inletconduithaving-oneend portion mounted in the upper 'end of said tubehousing; an annular apertured conduit communicatively'connccted to saidinlet conduit and adapted to distribute impure fatty substancesthroughthe space "between said condenser tube and said'tube housing andalong the inner annular face of said tube housing; an exhaust :outletfitting having an inwardly extending curved baffle-flange mounted in thesaid aperture. of said tube housing, said flange being adapted to divertdownwardly flowing fatty material from the aperture of said fitting; abasin of greater diameter than the diameter of said condenser :tube andbeing below the-lower end of said condenser tube and having an outletpipe extending through :the wall of said tube housing, whereby condensedimpurities may 'be discharged, "said tube housing providing a :reservoirbelow said funnel member for the collection of purified ffats fromthe'inner wall of said tube housing :andia conduit extending from saidreservoir through said tube housing and for-exhausting thepurified fatsfrom said reservoir, the fat introduced by said inlet conduit beingadapted to gradually descend :and flow downwardly :along the inner faceof said tube housing, and said heating elements being adapted tovaporize the impurities of said fat of the introduced fat, saidcondensertube being adapted to condense a portion of the impurities, theremainder of said impurities being exhausted through said fitting.

3. .In a device for the continuous removal of volatile "impurities fromfats and the like, an outermost closed ended evaporating tube providinga vacuum chamber in which fat will move along a given course; a conduitextending through the upper portion of said tube for introducingitheunfinishedfat into the upper end of said vacuum chamber; an aperturedannular distributor connected to said fat conduit for distributing said.fat over the upper innersurface of said vacuum chamber; a steam heater=disposed around said vacuum chamber and being adapted to heat portionsthereof to the approximateijtemperature of said steam heater; a secondheater disposed around portions of said vacuum chamber and spaced belowsaid steam heater and being adapted to heat portions thereof tosubstantially the temperature of said second heater; said steam heaterbeing adapted to heat the vacuum chamber to temperatures which are lcwerthan the temperatures of said second heater; a condenser pipe in saidvacuum chamber providing a surface on which fluids may condense; theheatlfrom said second heater being adapted to drive ofi impure fluidsnot driven off by the heat produced by said primary steam heater; anexhaust nipple having a curved hanged end portion extending through saidevaporating tube and adapted to withdraw from said vacuum chamber allnon-condensable fluids, the condensable fluids being condensable alongsaid condensing surface; said nipple being disposed on the inner wall ofsaid tube and-adapted to keep fats from being withdrawn through saidnipple; a fluid collection means adapted to collcct the condensed fluidsfrom saidcondensin'g 9 surface and conduct them out of said vacuumchamber; a reservoir in the bottom part of said vacuum chamber adaptedto collect the finished fats, and conduit means connected with saidreservoir for continuously removing the finished fats.

JOHN E. THOMPSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

NUIIlbBI Number Great Britain June 24, 1938

1. IN A DIVICE FOR THE CONTINUOUS REMOVAL OF VOLATILE ELEMENTS FROM FATSAND THE LIKE, AN OUTER HOUSING PROVIDING THE OUTERMOST WALL OF A VACUUMCHAMBER AND PROVIDING AN INNER SURFACE ALONG WHICH FATS WILL FLOWDOWNWARDLY; PIPE MEANS EXTENDING THROUGH SAID HOUSING FOR INTRODUCINGTHE UNFINISHED FAT INTO UPPER PORTIONS OF SAID VACUUM CHAMBER; ACIRCULAR CONDUIT HAVING A PLURALITY OF HOLES AND BEING CONNECTED TO SAIDPIPE MEANS FOR DISTRIBUTING SAID FAT OVER THE UPPER INNER SURFACE OFSAID OUTER HOUSING; A STREAM HEATER DISPOSED AROUND SAID VACUUM CHAMBERAND BEING ADAPTED TO HEAT PORTIONS THEREOF TO THE APPROXIMATETEMPERATURE OF SAID HEATER MEANS; AN ELECTRICAL HEATER DISPOSED AROUNDPORTIONS OF SAID VACUUM CHAMBER BELOW SAID PRIMARY HEATER AND BEINGADAPTED TO HEAT PORTIONS THEREOF TO SUBSTANTIALLY THE TEMPERATURE OFSAID SECOND HEATER MEANS, SAID PRIMARY HEATER BEING ADAPTED TO HEAT THEVACUUM CHAMBER TO TEMPERATURES WHICH ARE LOWER THAN THE TEMPERATURES